stream: event contract

[ronag]

Try to follow the assumed "contract"/"api" in terms of stream events:

events (only close after error, nothing after close, only error or close after destroy)

• don't emit finish on error (stream: don't emit finish on error #28979)
• document when destroy emits events (doc: clarify when destroy emits events #28970)
• don't emit open after destroy ([x] fs: don't emit open after destroy #28765)
• don't emit after 'error' (stream: don't emit after 'error' #28708)
• don't emit finish on error (stream: don't emit finish on error #28979)
• eos premature close (stream: eos premature close #28720)

[Fishrock123]

Are these supposed to be check off?

[ronag]

I checked them when there was a PR. But maybe it makes more sense to check them when it's been merged.

[ronag]

I'm moving this into my own list and will open PR's accordingly when my number of open PR's drop.